Another way to make solar a little bit cheaper.

Want to add solar to your roof? You’ll need a permit for that. And it could cost you.

Like any other major home renovation, installing solar panels usually requires a permit from your town or county. Some require just a few pages of paperwork, others a whole stack. And the fees involved vary widely.

How much? A study released last year by the Sierra Club found that solar permit fees in Northern California ranged from nothing to $888. In SoCal, a handful of cities charged more than $1,000.

Now, granted, if you’re willing to spend $25,060 on a home solar system (the rough average for a 3.5kw system in California these days, according to state data), $888 won’t be a deal-breaker. But it’s still $888.

So on Thursday, Gov. Jerry Brown signed a bill capping those fees at $500 for most residential solar systems. The law goes into effect in January.

According to that Sierra Club study, only 7 percent of the Northern California municipalities surveyed charged more than $500. The new law, therefore, isn’t a big step.

But it’s something. As the price of solar panels has plunged in recent years, the industry has focused on trying to cut its “soft costs” — all the things like paperwork and permit fees that have nothing to do with equipment or labor.

Some Bay Area cities are trying to coordinate their solar permitting processes. SolarTech, an industry consortium based in San Jose, is pursuing the idea as well. Even the federal government is taking a look.

The new law, penned by California Sen. Mark Leno, doesn’t standardize the permitting process. It just adds a little more predictability to the fees and reins in those cities charging far more than others. You can read the law’s text and summary here.